1. Field of the Invention
The invention relates to polishing apparatus.
2. Description of Prior Art
The invention relates more particularly to polishing (and lapping) apparatus particularly for finishing planar surface of various materials such as quartz, ceramics, ferrite, piezoelectric elements semi-conductor wafers, oxide wafers, carbon, metals and super-hard compounds. Typically, the polishing apparatus comprises a lower circular flat disc and an upper opposing circular flat disc that is relatively rotated about a common axis. The opposing surfaces are covered or coated with cloth or other similar material and the components that are to be polished supported in a carrier that is arranged to be rotated in planetary fashion by the relative rotation of the discs. Such an arrangement is well-known.
During polishing, particles removed from the surfaces of the components and residue to polishing pastes or other fluids is deposited on to the cloth surfaces of the discs. It is known to provide a bristled carrier, to replace the component carrier, that serves to clean the polishing surface of the discs. At present the bristled carrier has a plurality of clumps of bristles protruding beyond each its surfaces, the top and bottom surfaces, of the carrier disposed in a spiral array. As the polishing apparatus is operated, the bristled carrier is driven in planetary fashion to brush-clean the clothed surfaces of the discs. The bristles are permanently attached to the carrier and when the bristles wear down or become otherwise non-serviceable, the bristled carrier has to be discarded in toto. This makes replacing the carriers relatively expensive and, as it is sometimes desirable to have different cleaning bristles for different applications, (i.e. harder/stronger bristles are sometimes required), this means that each of the present bristled carriers have minimum versatility.